<!DOCTYPE html>
<style>
option {
    /* Default properties */
    background-color: lightgreen;
    color: red;
    padding-left: 20px;
}
option:checked {
    background-color: green;
    text-decoration: underline;
}
</style>
<select multiple>
    <option>foo</option>
    <option selected>bar</option>
</select>
